python 判断一个类或实例是否继承自某类

def ischildof(obj, cls):
    try:
        for i in obj.__bases__:
            if i is cls or isinstance(i, cls):
                return True
        for i in obj.__bases__:
            if ischildof(i, cls):
                return True
    except AttributeError:
        return ischildof(obj.__class__, cls)
    return False

isSubClassOf = ischildof

简单测试可行